Electrical switch



Aug. 9, 1960 D. H. LANCTOT ELECTRICAL SWITCH 2 Sheets-Sheet 1 Filed Feb2, 1959 IIII'II' IIIIIIII INVENTOR. DONALD H. LANCTOT e gmw fldz 'w Aug.9, 1960 Filed Feb. 2, 1959 D. H. LANCTOT 2,948,793

ELECTRICAL SWITCH 2 Sheets-Sheet 2 INVENTGR. DONALD H. LANCTQT' BYQAMYQ%7&%/ ATTORNEYS ELECTRICAL swrroH Donald Lanctot, Malibu, Califi,assignor to Don-Lan Electronics Co., Inc., a corporation of CaliforniaFiled Feb. 2, 1959, Ser. No. 790,715

7 Claims. or. 200- 163) This invention relates generally to electricalswitches ami more particularly to manually operable miniature switchesfor switching high frequency electrical energy.

One of the more troublesome problems in electrical switches resides inthe making or breaking of a reliable electrical contact between theconductors to be connected or disconnected. Generally, switches employsome type of contact arm including a conducting portion arranged toconnect the two conductors upon movement in one direction and todisconnect the conductors upon movement in an opposite direction. In thecase of switches which are subject to severe environmental conditionssuch. as excessive shocks and vibrations, it is very important tomaintain a high contact pressure when conductors are connected together.Moreover, contact bounce and poor conductivity after prolonged use as aconsequence of. dirt, grit, corrosion, and the like at the contact areasshould be minimized.

Bearing the. foregoing in mind, one object of the present invention isto provide an improved electrical switch which is capable ofwithstanding relatively severe shocks and vibrations.

Another important object is to provide a switch in which a high contactpressure is always maintained when the switch is in its on position.

Still another object is to provide a novel switching contactvarrangement providing both the desired high contact pressure andself-cleaning action to the end that a high degree of conductivitythrough the switch when in its on position is maintained over anextended period of life.

More general objects of the invention are to provide miniaturized highfrequency switches of compact, light weight, and economicalconstruction.

Briefly, these as well as many other objects and advantages of thisinvention are attained by providing a basic casing structure having atransverse passage. Suitable input and output connectors or otherconducting bodies to be connected together extend into the casing andterminate in inner ends adjacent opposite sides of the transversepassage. A single integral switching bar along the axis of the passage.a sm all ring made of highly conductive material.

of the passage and the inner contacting ends of the con ductors at theirtermination pointson the passage. 7

By the foregoing arrangement, movement of the.

switching bar in a given direction will cause the conducting ring tomove between the inner ends of the conductors to electrically connectthe same. The spacing between. the inner ends ofthese conductors is madeslightly less than the outside diameter of the ring so that-upon urgingof the ring between .the inner conductors, the ring itself isdistortedto asomewhat oval'shape, thereby. result-ing;

in a relatively high contactipressure;between substaru tiallyopposite.diametricahpoints on,the ring and the 70 ernd? the n e ns e rssveln The ring is preferably supported within a longitudinal oppositesides of ice slot in the switching bar. The inside wall surfaces of thetransverse passage retain the ring within the slot and yet the ring isfree to roll or move slightly within the slot. With this type of supportfor the ring, urging of the same between the inner ends of theconductorswill result in slight rolling movements of the ring as well'as the heretofore referred to squeezing action to distort the same andas a consequence, the contacting surfaces are self-cleaning. Moreover,as a further consequence of the intentional distortion of the'ring whenin contact with the inner ends of the conductors, there is no;

possibility of contact bounce or the like and the entire structure willmaintain an excellent electrical connec tion even under relativelysevere shocks and vibrations.

By extending the length of the switching bar and pro.- viding additionalrings, multiple pole multiple throw' switches may be provided.

A better understanding of the invention will be had. by referring to thepreferred embodiments thereof as v illustrated in the accompanyingdrawings, in which:

Figure 1 is an overall perspective view of a first em-- bodiment of theelectrical switch of this invention;

Figure 2 is an elevational cross sectional view taken in the directionof the arrows 22 of Figure 1 showing: the switching bar in its onposition;

Figure 3 is a View similar to Figure 2 illustrating the switching bar inits 05 position.

Figure 4 is an enlarged fragmentary view partly in. cross section takenin the direction of the arrows 4-4- of Figure 1;

Figure 5 is an exploded perspective view of the switch-- ing bar andconducting ring portions of the switch of Figures 1, 2, and 3;

Figure 6 is a perspective view of a second embodiment: of the switch ofthis invention;

Figure 7 is an elevational cross sectional view taken; in the directionof the arrows 7-7 of Figure 6 showing the switching bar in a firstposition; and,

Figure 8 is another elevational cross sectional View similar to Figure 7illustrating the switching bar'in' a. second position.

Referring tothe embodiment of Figure 1, there is: shown a casing 10having an input conductor or probe 11 and a threaded co-axial connector12 on one side; and an output conductor 13 and threaded co-axial con--nector 14 on the opposite side. A switching bar 15 ex tends transverselythrough the casing 10 Within a transverse passage or bore 16 as seen inFigure 2. The ar-' rangement is such that the switching bar 15 can bemanually moved back and forth within the transverse passage between theposition illustrated in solid lines in Figure l to the positionillustrated in dotted lines at 15-.

Referring particularly to Figures '2, 3, 4, and 5, the details of thecasing structure and switching bar-are illustrated. As shown, the innerconductor or probes 11' and 13 are co-axially supported within thethreaded 9 connecting portions 12 and 14 by a single head of di electricmaterial 17. The right hand end of the head is retained in sealedposition against the threaded con necting input portion 12 as by aninsulating annular washer 13. The central portion of the bead includes atransverse bore 19 registering with the transverse passage 16 of thecasing 10 for receiving the switchingbar 15.

The ends of the passage 16 Within the casing 10 tormie nate in annularrecesses defining shoulders such as indicated at 2 1 and 21 forco-operation with end knobs 22 and 23 of the switching bar. Theseshoulders serve as:

stops. for limiting movement of the switching bar backs. and forththrough the transversepassage, 1'5 .asswill-bea evident from Figures 2and. 3, respectively.

In order to secure the the other, the casing is provided with a lateralbore 24 as best seen in Figures 1 and 4. This bore includes a small ball25 at its innerend biased towards the central passage 16 by a spring 26and a set screw 27. The upper end of the switching bar as best seen inFigure 5 in turn is provided with a pair of axially spaced annulargrooves 28 and 29. The arrangement is such that the annular groove 28will receive the ball when the switch is in the position illustrated inFigures 2 and 4. When the switch is moved to the position illustrated inFigure 3, the ball 25 will then be received in the annular groove 29.This biasing feature, therefore, serves as an indexing means for theswitching bar in each of its manually moved positions.

The switching bar 15 as shown in Figlre 5 also includes an axial slot 30arranged to support and carry a conducting ring 31. The entrance andexit width and length dimensions of the slot 30 are slightly greaterthan the width and outside diameter of the conducting ring 31respectively such that the ring may be readily received and moveslightly within the slot. The outside diameter of the switching bar atthe slot portion, however, is less than the normal diameter of the ringso that diametrically opposite peripheral portions of the ring extendfrom the entrance and exit portions of the slot.

Referring again to Figures 2 and 3, it will be noted that with theconducting ring 31 in the slot 30, the ring will beretained in the slotby the side walls of the bore 16; The ring is positioned such that itsaxis is normal to the axis of the transverse passage so that when theswitching bar 15 is moved to the position illustrated in Figure 2opposite diametrical portions of the ring 31 will engage the innercontacting ends 32 and 33, respectively, on the inner conductors 13 and11. The spacing between these inner contacting ends 32 and 33 isslightly less than the outside diameter of the conducting ring 31 sothat upon urging of the conducting ring between the contacting ends, thering will become slightly distorted within the slot 30 and provides ahigh contact presure at the diametrically opposite portions of the ringagainst the contacting areas of the inner ends.

When the switching bar 15 is moved from the position illustrated inFigure 2 to that shown in Figure 3, the ring 31 is moved from betweenthe opposed inner contacting ends thereby electrically opening theswitch.

As shown in both Figures 1, 3, and 5, at least a portion of theswitching bar 15 is provided with a flat surface as indicated at 34. Acorresponding side wall 35 of the transverse passage 16 is also flat toregister with the flat portion 34 as shown in Figure 3 so that theswitching bar 15 is prevented from rotating about its own axis withinthe passage 16.

The operation of the switch from the foregoing description will beevident. When the switching bar 15 is moved to the position illustratedin Figure 2, by manually depressing the knob 23, the input conductor 11is electrically connected through the conducting ring 31 to the outputconductor 13. Because of the distortion of the conducting ring 31 whichwill maintain a high contact pressure at the inner contacting ends 32and 33 of the conductors, the switching bar 15 will by friction beretained in place. However, the action of the small ball 25 shown inFigure 4 within the annular groove 28 Will further insure retention ofthe switching bar in the position illustrated in Figure 2.

When it is desired to disconnect the inner conductors, the switching bar15' is manually pushed upwardly by exerting pressure on the lower knob21 to the position illustrated in Figure 3 wherein the small ball 25 ofFigure 4 will now be received within the annular groove 29. In thisposition, it will be evident that the conducting ring 31 is totallydisengaged from the inner contacting ends of the two conductors 11 and13 and, therefore, the electrical connection is broken.

switching bar in one position or Moreover, because the switching baritself is of an insulating material it may be constructed of a lightplastic or the like and this feature in combination with the relativelysmall annular conducting ring provides a relatively light total mass forthe moving part of the switch. As a consequence, severe vibrations andhigh shock loads of the switch will not appreciably affect the desiredpositioning of the switching bar.

Referring now to Figures 6, 7, and 8, there is illustrated a secondembodiment of the invention in which the fOTC',

going principles are provided in a double pole double throw switch.

In Figure 6, there is shown a main casing 37 having input connectors 38and 39 and four output lugs or terminals 40, 41, 42, and 43 extendingfrom an opposite side of the casing 37. As in the case of the embodimentof Figure 1, there is provided a switching bar 44 operable in atransverse bore extending through the casing 37 for effecting thedesired switching action.

Referring to Figures 7 and 8, the inner input conductors of theconnectors 38 and 39 are indicated at 45 and 46 and are hereinafterreferred to as first and second input conductors. These conductorsterminate in inner contacting ends 47 and 48 of relatively increaseddimension along the axis of the passage receiving the switching bar 44.These input conductors as well as the various output conductorsterminating in the terminal lugs 40, 41, 42, and 43 are insulativelysecured within the casing 37 by annular beads 49 and 50 of di-electricmaterial.

At the top opening portion of the central passage of the casing 37,there is provided a collar 51 having a bore receiving a small ball 52biased by a spring 53 and a set screw 54. This ball co-operates withannular grooves such as indicated at 55 in Figure 7 and 56in Figure 8 toretain the switching bar 44 in one position or the other.

As shown in both Figures 7 and 8, the switching bar 44 includes twolongitudinal slots 57 and 58 for carrying a conducting ring 59 and anadditional conducting ring 60 axially spaced a given distance along theswitching bar 44 corresponding substantially to the spacing between theinner contacting ends 47 and 48 of the first and second input conductors45 and 46. As in the case of the embodiment of Figures 1 through 5, theswitching bar 44 is also provided with a flattened outside surface area61 along at least a portion of its length for cooperation with asimilarly flattened inside wall portion 62 of the transverse bore in thecasing 37. By this arrangement, relative rotation of the switching 'bar44 and casing 37 is prevented.

In the particular embodiment chosen for illustrative purposes in Figures7 and 8, the lugs 41 and 43 constitute the end portions of first andsecond output conductors having inner ends 63 and 64 respectivelypositioned adjacent the longitudinal passage on opposite sides from theinner ends 47 and 48 of the first and second input conductors 45 and 46.

The terminal lugs 40 and 42, on the other hand, constitute the ends ofadditional output conductors having inner ends 65 and 66 spacedrespectively from the inner ends 63 and 64 a given distance no greaterthan the distance through which the switching bar 44 may be moved.

By the foregoing arrangement, and with the switching bar 44 in theposition illustrated in Figure 7, it will be noted that the inputconductors 45 and 46 are each respectively connected through theconducting rings 59 and 60 to the output conductor terminal lugs 41 and43, while the output terminal lugs 40 and 42 are disconnected. When theswitching bar 44 is moved upemerge Wardly to the position illustrated inFigure 8, the same input conductors 45 and 46 are connected through therings 59 and 60, respectively, to the additional output conductor lugs40 and 42 and the terminals 41 and 43 of the first mentioned first andsecond output conductors are disconnected.

As in the case of the embodiment of Figures 1 through 5, the spacingbetween the inner ends of the various conductors is slightly less thanthe outside diameter of the rings 59 and 60 so that slight distortion ofthe rings is efiected when they are moved between the contacting ends.Thus the advantages heretofore stated of high contact pressure andminimization of interference by vibrations and shock obtain in thedouble pole double throw configuration as described.

A particular advantage of the embodiment of Figures 6 to 8 resides inthe exact switching synchronism between the input conductors and therespective output conductors. This synchronisrn is maintained as aconsequence of the use of a rectilinear switching bar structure whichmoves in the direction of its longitudinal axis. Thus, internalcontraction or expansion from switching pressure is negligible and noflexure deformations come into play. Therefore, the spacing between therings remains fixed at all times.

From the foregoing description, it will be seen that the presentinvention provides greatly improved electrical switches. Not only arethe devices extremely reliable as a consequence of the unique provisionof the conducting ring within the switching bar, but the entireassemblies can be made relatively small and of compact form.

Modifications that fall within the scope and spirit of this inventionwill readily occur to those skilled in the art. The electrical switchesare, therefore, not to be thought of as limited to the particularembodiments chosen merely for illustrative purposes.

What is claimed is:

l. A switch comprising: a casing filled with dielectric material andhaving a transverse passage extending therethrough; a movable switchingbar disposed in said passage; two conductors extending into oppositesides of said casing and dielectric material and having their inner endsterminating adjacent to opposite sides of said passage and their outerends extending to the exterior of said casing, said dielectric materialrigidly securing said inner ends in a fixed position so that the spacingbetween said inner ends is held constant; and a conducting ring ofresilient material coupled to said switching bar within said passage andlying in a plane including said inner ends and the axis of movement ofsaid switching bar, said spacing between said inner ends of said twoconductors being less than the outside diameter of said ring, wherebymovement of said switching bar in one direction urges said ring betweensaid inner ends to electrically connect the same, and resilientlydistorts said ring into an oval to apply contact pressure atsubstantially diametrically opposite portions of said ring in engagementwith said inner ends, and movement of said switching bar in an oppositedirection removes said ring from between said inner ends.

2. The subject matter of claim 1, in which said switching bar is ofinsulating material and includes a longitudinal slot of entrance andexit width and length dimensions at least as large as the width andoutside diameter of said ring respectively whereby said ring isreceivable in said slot.

3. The subject matter of claim 2, in which the ends of said switchingbar extend out of said passage to the exterior of said casing to beexposed for manual movement in either direction.

4. The subject matter of claim 3, in which said switching bar includes apair of axially spaced annular grooves, said casing including indexingmeans biased against a side of said switching bar, the axial spacingbetween said grooves corresponding to the movement of said switching barwhereby' said indexing means is receivable in each of said grooves tohold said switching bar in given positions.

5. A switch comprising, in combination: a casing filled with dielectricmaterial and having a transverse passage extend therethrough; aswitching bar supported in said passage for back and forth movementalong the axis of said passage; a resilient ring of conducting materialsupported by said switching bar within said passage and positioned withits axis normal to said axis of said passage; a first input conductorextending into said dielectric material and having an inner contactingend positioned adjacent one side of said passage, said dielectricmaterial rigidly securing said end in a fixed position; and a firstoutput conductor extending into said dielectric material and having aninner contacting end positioned adjacent an opposite side of saidpassage, said dielectric material rigidly securing said last mentionedend in a fixed position so that the spacing between the contacting endsof said input and output conductors is held constant, the outsidediameter of said ring being greater than said spacing, whereby movementof said switching bar in one direction moves said ring to distort saidring into an oval shape between the contacting ends of said input andoutput conductors to distort said ring into an oval shape and therebyelectrically connect said input conductor to said output conductor andmovement of said switching bar in an opposite direction causes said ringto disengage at least the inner contacting end of said first outputconductor.

6. The subject matter of claim 5, including an additional resilient ringof conducting material supported by said switching bar within saidpassage a given axial distance along said passage from said firstmentioned ring; and a second input conductor extending into saiddielectric material and having an inner contacting end positionedadjacent said passage at a point axially spaced said given axialdistance from the inner end of said first input conductor; and a secondoutput conductor extending into said dielectric material and having aninner contacting end positioned adjacent to an opposite side of saidpassage from said inner end of said second input conductor, saiddielectric material rigidly securing said contacting end of said secondinput conductor and said contacting end of said second output conductorin fixed po sitions so that the spacing therebetween is held constant,the outside diameter of said additional ring being greater than saidlast mentioned spacing, whereby movement of said switching bar in saidone direction simultaneously moves said additional ring between saidcontacting ends of said second input and output conductors to distortsaid additional ring and electrically connect said ends of said secondinput and output conductors and movement of said switching bar in saidopposite direction causes said additional ring to disengage at least theinner contacting end of said second output conductor.

7. The subject matter of claim 6-, in which the inner ends of said firstand second input conductors have elongated surfaces in the direction ofmovement of said switching bar to maintain contact with said firstmentioned and additional rings respectively when the same are moved outof engagement with the inner ends of said first and second outputconductors respectively; and two additional output conductors extendinginto said dielectric material and having inner ends disposed in aposition to engage said first mentioned and additional ringsrespectively when said switching bar is moved to said position out ofengagement with the inner ends of said first and second outputconductors whereby a double pole double throw switch is provided.

References Cited in the file of this patent UNITED STATES PATENTS1,889,515 Hammerly Nov. 2,9, 193;

